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![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(188.79999999999998, 19%, 28%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EVM%3C/text%3E%3C/svg%3E)
I created a very simple console app with a library that I am having problems referencing from the console app to the library.
You can see by the picture that everything is set up I think correctly and there is a reference to the library.
When I hover over the red line it shows the air cs0246 the type or namespace name car could not be found are you missing a using directive or an assembly reference? in the picture I hit previous change and this is what you see.
I must be overlooking something but cannot figure it out.
I am using visual studio 2019, a standard classic 2.1 Library and a console app framework 3.1
Is the class Car in a namespace contained in the OldCarLibrary assembly? Maybe the using statement needs to refer to it.
Hi vick myers,
Using the same version of the .net framework to create the library and the console program should not have this problem, I suggest you try it.
Thank you RLWA32: Yes for the Car in a namespace but it doesn't help
I'm assuming that the red squiggles are from intellisense. Does an actual build of the console application fail?
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(211.20000000000002, 61%, 30%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EBS%3C/text%3E%3C/svg%3E)
has OldCarLibrary built without errors? try a rebuild
Yes I rebuild the OldCarLibrary with no problem, but I still have the reference issue.
I tried to reproduce your issue and found that browsing to the.net standard assembly and adding a reference directly instead of a reference to the project enabled a console application to build successfully. That's the good news. But the console application crashed during execution when the system could not find.net standard system dlls in the GAC.
The easy fix is to have all projects use the same .NET Framework rather than one classic and one .NET Standard. So one of them needs to be recreated to match the other project framework.
Karen thank you, before I read your statement, I switch out the library with a framework library. visual studio has a few to choose from and that is what fix my issue. Thank you very much.
The real problem is that .Net Standard 2.1 is not supported by the .Net Framework. Refer to https://learn.microsoft.com/en-us/dotnet/standard/net-standard?tabs=net-standard-2-1. However, if you target your class library to .Net Standard 2.0 then it can be consumed without problem by a .Net Framework application. The supported versions of the .Net Framework are documented at https://learn.microsoft.com/en-us/dotnet/standard/net-standard?tabs=net-standard-2-0.